code: def forward(self, x):
      x = self.conv1(x)
      x = self.bn1(x)
      x = self.activation(x)
      x = self.conv2(x)
      x = self.bn2(x)
      x1 = self.activation(x)  # N x 32 x 256 x 256
      x = self.conv3(x1)
      x = self.bn3(x)
      x2 = self.activation(x)  # N x 64 x 128 x 128
  
      x3 = self.layer1(x2)  # N x 64 x 128 x 128
      x4 = self.layer2(x3)  # N x 128 x 64 x 64
      x5 = self.layer3(x4)  # N x 256 x 32 x 32
      x = self.layer_bottleneck(x5)  # N x 512 x 16 x 16
  
      return x, (x1, x2, x3, x4, x5)
  
imports: import paddle
  import paddle.nn
  import paddle.nn.functional
  from paddleseg.cvlibs import manager, param_init
  from paddleseg.utils import utils
  from ppmatting.models.layers import GuidedCxtAtten
label_desc: Use image node_id 3 for calling the ResNet_D obj's underlying member method code with example usage: obj.forward(x) and returns: x,  x1,  x2,  x3,  x4,  x5